83 years ago today
Albert Hofmann Accidentally Discovers LSD
On April 16, 1943, Swiss chemist Albert Hofmann was working at Sandoz Laboratories in Basel when he accidentally absorbed a small amount of lysergic acid diethylamide — a compound he had first synthesized five years earlier — through his fingertips. He began experiencing unusual sensations and vivid imagery, realizing he had encountered a substance of extraordinary psychoactive potency. Hofmann intentionally repeated the experiment three days later on April 19 to confirm the effects, ingesting what he considered a small dose of 250 micrograms and riding home by bicycle during the experience that later became known as "Bicycle Day." The discovery launched an entirely new field of psychedelic research and, decades later, profoundly influenced psychiatry, neuroscience, and counterculture alike. Hofmann himself called LSD his "problem child" in a famous memoir, but never stopped believing it held legitimate therapeutic value.
This day, across time
- 69 CEDiedEmperor Otho
- 73 CEEventFall of Masada
- 1346EventStefan Dušan Crowned Emperor of the Serbs
- 1520EventRevolt of the Comuneros Begins in Spain
- 1746EventBattle of Culloden
- 1755BornLouise Élisabeth Vigée Le Brun
- 1844BornAnatole France
- 1853EventFirst Passenger Railway in India Opens
- 1862EventDC Emancipation Act Signed
- 1867BornWilbur Wright
- 1889BornCharlie Chaplin
- 1912EventHarriet Quimby Flies the English Channel
- 1917EventLenin Returns to Russia from Exile
- 1943FeaturedAlbert Hofmann Accidentally Discovers LSD
- 1945EventRed Army Launches Final Assault on Berlin
Alive in 1943
OverlapSame years; not influence
Nikola Tesladied this year
Abraham Heschelturned 36 this year- Adolf Hitlerturned 54 this year
Albert Einsteinturned 64 this year
Carl Gustav Jungturned 68 this year
Deng Xiaopingturned 39 this year
Eleanor Rooseveltturned 59 this year
Elvis Presleyturned 8 this year
Emmanuel Levinasturned 37 this year
Ernest Hemingwayturned 44 this year
20 more figures were alive that year
On This Day in History
10 EventsFall of Masada
The Jewish fortress of Masada falls to Roman forces after a months-long siege, ending the First Jewish–Roman War. According to Josephus, nearly one thousand defenders chose death over captivity.
Stefan Dušan Crowned Emperor of the Serbs
Stefan Dušan, known as "the Mighty," is crowned Emperor of the Serbs at Skopje, presiding over an empire that stretched across much of the Balkans.
Revolt of the Comuneros Begins in Spain
A major uprising against the rule of Charles V breaks out in Castile, as urban communities — the comuneros — resist the new king's foreign advisors and tax demands.
Battle of Culloden
The last pitched battle on British soil is fought on Culloden Moor in Scotland. The Jacobite forces of Bonnie Prince Charlie are decisively crushed by the Duke of Cumberland's Hanoverian army, ending the Stuart cause forever.
First Passenger Railway in India Opens
The Great Indian Peninsula Railway inaugurates India's first passenger rail service, running from Bori Bunder in Bombay to Thane — a journey of about 21 miles that drew cheering crowds of thousands.
DC Emancipation Act Signed
The District of Columbia Compensated Emancipation Act is signed into law, freeing approximately 3,100 enslaved people in Washington D.C. — the only compensated emancipation in U.S. history, occurring nine months before the Emancipation Proclamation.
Harriet Quimby Flies the English Channel
American aviator Harriet Quimby becomes the first woman to fly an airplane across the English Channel, completing the 22-mile crossing in under an hour.
Lenin Returns to Russia from Exile
Vladimir Lenin arrives in Petrograd from exile in Switzerland, traveling in a sealed train arranged by Germany. His return transforms the Russian Revolution and leads within months to the Bolshevik seizure of power.
LSD Accidentally Discovered
Swiss chemist Albert Hofmann accidentally absorbs LSD-25 through his fingertips at Sandoz Laboratories, discovering its powerful psychoactive effects. His famous intentional self-experiment and bicycle ride followed three days later, on April 19.
Red Army Launches Final Assault on Berlin
Nearly one million Soviet troops begin the Battle of the Seelow Heights, the last major defensive line before Berlin, marking the beginning of the end for Nazi Germany.
Born on This Day
Charlie Chaplin
Actor, Filmmaker & Comedian
Born in London, Charlie Chaplin became one of the most influential figures in cinematic history, creating the iconic Tramp character in the silent film era. His films blended physical comedy with sharp social commentary, and works like The Great Dictator and Modern Times remain masterpieces of world cinema.
Wilbur Wright
Aviation Pioneer
The elder of the Wright brothers, Wilbur co-invented the world's first successful powered airplane with his brother Orville, achieving the historic flight at Kitty Hawk in 1903. His meticulous engineering and experiments with aerodynamics laid the foundation for modern aviation.
Anatole France
Novelist & Nobel Laureate
French author Anatole France was one of the most celebrated writers of the late 19th century, known for his ironic wit and opposition to injustice — including his public support of Dreyfus. He was awarded the Nobel Prize in Literature in 1921.
Louise Élisabeth Vigée Le Brun
Painter
One of the most successful female painters of 18th-century Europe, Vigée Le Brun was the official portraitist to Marie Antoinette and produced over 600 paintings. She was among the few women admitted to the Royal Academy of Painting and Sculpture.
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Emperor Otho
Roman Emperor
Defeated by Vitellius at the Battle of Bedriacum, the Roman emperor Otho chose suicide over further civil war, having reigned for just 95 days. His death was regarded by ancient historians as surprisingly dignified.
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